Letter Chart

A Letter Chart, commonly used in eye exams, displays rows of letters that decrease in size from top to bottom. During the test, you read aloud the smallest line you can see clearly, which helps determine your visual acuity—the clarity of your vision. The chart typically uses a standardized font called Sloan letters, and the results guide eye care professionals in diagnosing and correcting your vision problems. It’s a simple, effective tool to assess how well you see at various distances, usually at a standard distance of 20 feet.